ENZYME KINETICS AND MECHANISM: THE EFFECTS OF ADENOSINE-NUCLEOTIDE DERIVATIVES ON ADENOSINE DEAMINASE

Ayesha Amin, Omkar Baxi, Laura Gay, Neha Limaye, Andrew Massaro, Daniel Nachajon, Albert Ng, Melanie Pastuck, Tara Weigand, Rose Yu

Advisor: Dr. Adam G. Cassano
Assistant: Jennifer Cowell

ABSTRACT

In this study we investigated the nature of the active site on the enzyme adenosine deaminase ( ADA ) in hopes of finding an analog structure to act as an inhibitor. Our research involved comparing the binding patterns of adenosine to several structural analogs by analyzing and comparing kinetic and spectroscopic data. We examined variations in positions 2 and 6 of the carbon ring to determine if either structural change may result in inhibition. 2-chloroadenosine was used to examine the 2-position, and similarly, 6-chloroadenosine and N-6-cyclohexyladenosine were used to consider the 6-position. The V max and K M values were established from data analysis with the Michaelis-Menton equation, and were used to compare adenosine and 6-chloroadenosine, which is observed to act as a substrate. The K M for adenosine was found to be 11.85 µM and the V max was determined to be 6.8x10 -9 M/s. Both 2-chloroadenosine and N-6-cyclohexyladenosine were found not to bind at all, suggesting that structural alterations at either location would not yield inhibition. However, the possibility exists of smaller alterations at the 6 position leading to ADA inhibition.